In a wireless communication network, communication is established between a node and a plurality of mobile devices. Typically, communication is established over a link known as an uplink/downlink for communicating data between the node and a mobile device. However, such a link weakens as the mobile device travels to the edge of a cell or to another cell, and as a result the mobile device may have discontinuous communication with the node. The mobile device therefore establishes a new link with a node in a neighboring cell when the mobile device tends to travel to the corresponding neighboring cell. The mobile device however, prior to establishing such a new link, performs mobility measurement on one or more of the neighboring cells. Such measurement may be a general measurement of a total power received from a transmitter of the node located at the neighboring cell.
Upon performing mobility measurement on the neighboring cells, the mobile device selects a cell, or makes a report to facilitate selection of a cell, that has an optimized communication configuration. For example, the selected cell may have a maximum power level and so is the best neighboring cell to provide uninterrupted or continuous communication between the node and the mobile device.
In the existing technique, the mobile device receives unicast subframes from each node in the neighboring cells and performs mobility measurements over such received unicast subframes. The mobility measurement is for only unicast subframes as only one type of transmission known as unicast transmission occurs in the communication network. However, the technology has been upgraded and in some instance, the neighboring cell may support both unicast and multicast subframe transmission, or hybrid combinations thereof. Multicast subframes include subframes comprising both unicast and multicast components, but at least a portion of the subframe is transmitted in a multicast fashion. Observations of a transmission, e.g., multicast transmission, in which multiple neighboring cells are participating, does not generally enable the mobile device to identify a specific individual and optimal neighboring cell, and indeed can lead to erroneous mobility measurement when such observations are treated as unicast observations. However, in a conservative measurement strategy, all transmissions comprising, in part, multicast transmissions, are neglected by the mobile device during mobility measurement. Such negligence may lead to increased mobile device mobility measurement activity and ultimately to higher power consumption by the mobile device when seeking to maintain specified mobility measurement accuracy, or to a loss of measurement accuracy. Thus, there is a need for the mobile device to perform mobility measurements for any type of subframe received in the communication network.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.